Rotary core-drill attachment



HELM Y17,. WQS. 1,656,809

A. L. ARMENTROUT ET AL ROTARY CORE DRILL ATTACHMENT Filed Nov. 18, 1925 IN1/EN T0125 Ae r//UE Eo/v ARME maar BY ELn//fv HALL W' A TTORNEYS..

lll

Patented Jan. 17, 1928.

UNITED STATES TEUR L. ENTR'UT AND ELWIN B. HALL, 0F MCKITTRICE'., CALHO.

ROTARY CORE-DRILL ATTACHMENT.

Application filed November 18, 1925. Serial No. 69,913.

@ur invention relates to rotary core drills of the character embodied in the application of Arthur L, Armentrout filed April 14, 1925, Serial No. 23,113, by which a sample core is formed and extracted to determine the character of the earth formation encountered. v

ln securing sample ores in this manner, the character of the earth, vas Well as the inclination of the formation, can be readily determined, but heretofore no means has been provided for determining the direction of the inclination. When prospecting for oil, the expense and time of drilling many holes may be saved if the approximate location of the crest of an anticline could be determined in the first drilling.

lt is a purpose of our invention to provide a device in the form of an attachment for rotar core drills of any conventional form by which can be determined the exact direction in which an inclined earth stratum extends whereby the crest of an anticline can be subsequently determined and reached by a single drilling operation.

We Will describe only one form of rotary core drill attachment embodying our invention and will thenV point out the novel features thereof in claims.

ln the accompanying drawings,

Figure 1 is a view showing in vertical section a rotary core drill in applied position Within the well and having ap v lied thereto one form of attachment embo ying our invention;

Figure 2 is a fragmentary sectional view taken on the line 2-2 of Figure 3;

Figure 3 is a fragmentary .s lan View of a compass dial and the locking devicetherefor.

Referring speciticallyto the drawings, in which similar reference characters refer to similar parts, our invention, in its present embodiment, is shown applied to a rotary core drill of the construction set forth in the application hereinbefore referred to, although it is to be understood that the invention is applicable to rotary core drills of any conventional form. The drill hereI shown includes boring bits l5 mounted in a tool head 16 connected to a tubular shank 17 through a connecting sleeve 18, a shank adapted to be rotated to effect rotation of the boring bits, and the tool head 16 being formed with a central opening 19 incommunication with a core barrel 20.

In the operation of the drill, the bits 15 operate to drill the hole while rotary cutters 21 in surrounding relation to the opening 19 of the tool head function to form a core 22 which, as the drill proceeds downwardly, passes upwardly into the core barrel 20. In keeping with the core drill embodied in the application hereinbefore referred to a movable sleeve 23 is mounted in the core barrel to directly receive the core.

The attachment embodying our invention comprises, in the present instance, a casing 24 secured at its lower closed end to a bracket 25, the latter, in turn, secured to the upper end of the core barrel 20. The upper end of the casing 24 is normally closed by a cover 26, and the casing is interiorly divided by means of partitions 27 and 28 into a plurality of compartments in which the devices constituting the attachment are housed. Within the lower-most compartment is a non-magnetic compass 29, preferably a gyroscoplc compass of the Sperry type includingthe conventional frame 29a having trunnions 29 by Which the compass as a unit is supported from the wall of the casing 24. This compass includes a motor 30 constantly driving the sensitive element of the compass, the latter being mounted to actuate a dial 31 disposed uppermost of the compass. The motor 30 is of the alternating current type and current is supplied thereto from an alternating current generator 32 driven by a direct current motor 33 with current supplied to the motor from a'battery By reference to Figures 2 and 3, it will be seen that the marginal edge of the dial 31 is formed with an annular series of teeth 35 adapted to be engaged by a dog 3G fixed to the angular extension 37 of a rod 38, the extension projecting through a suitable opening in the casing 2land the rod extending downwardly between the shank 17 and the core barrel 2O and through the tool head 16 to a point between certain of the boring bits 15. Guides 39 are provided to slidabl receive the rod 38, and as the rod has a sli ing lit in the tool head, it will be clear that the latter is capable of vertical movement to cause the dog 3G to engage or disengage the teeth 35 of the dial 31. When the dog engages the teeth of the dial, the latter is loc ed against rotation and by reference to Figure 2 it will be seen that the dog can seat Within a groove 40 ofa stationary rim member 41 of the compass frame 29, thus securlng the rod extension 37 against lateral movement. A spring 42 normally urges the rod 38 downwardly to cause the dog 36 to engage the teeth 35 and groove 40 to lock the dial against movement.

In o eration, the core drill rotates" continuous y in one direction to form the core 22, and with the drill in drilling position the projecting lower end of the rod 38 being in contact with the bottom of the well, holds the rod in elevated position against the action of the spring 42 to retain the dog 35 out of engagement with the dial 31. After the core has been completely formed, the drill is brought to rest, and after the lapse ot` a few seconds, during which the sensitive element of the compass can function to actuate the dial 3l so as to indicate due north. It will be noted that at the initiation of elevating movement of the drill from the well, the lower end of the rod 38, being elevated out of contact with the bottom of the well, permits the spring 42 to function in lowering the dog 36 in locking engagement with respect to the dial 3l, thus fixing the indication of the compass with respect to the strata of the core. The core drill is now elevated from the well, care being taken that the drill pipe is not rotated during this operation so that the compass will not be disturbed or possibly injured. By now unscrewing the sleeve 18 from the head 16 while maintaining the latter stationary, the pipe can be elevated from the attachment, after which a door 43 comrminicating with the gyroscope compartment can be opened to permit access to the dial 31. In noting the position of the inclined strata with respect to the north indication of the compass, it will be manifest that the exact direction in which the inclined strata extend can be accurately determined. lVith this factor determined, it will be clear that the location of the crest of the anticline can be subsequently determined and reached by a single drilling operation.

Although we have herein shown and de scribed only one form of attachment forrotary core drills embod ing our invention, it is to be understood tiat various changes and modifications may be made therein without departing from the spirit of the in'- vention and the spirit and scope of the appended claims.

W'e claim as our invention:

l. In combination, a core drill, a gyroscopic compass mounted thereon and including a dial, a member movably associated with the drill to occupy a. projected position with respect to the drilling end of the drill when the drill is in non-drilling position, and adapted to enga e the formation at the bottom of the hole wien the drill is in drilling position and be thereby moved to a retracted position and co-operative means on the member and dial for locking the dial against movement 'when the member is in projected position.

2. 4A combination as embodied in claim l wherein said means comprises teeth on the dial, and a dog fixed to the member and adapted to engage the teeth for locking the dial against rotation.

3. A combination as embodied in claim l wherein said means comprises teeth on the dial, and a dog fixed to the member and adapted to engage the teeth for locking the dial against rotation, said compass including a rim member having a groove therein adapted to be engaged by the dog when in locking position with respect to the dial to secure the dog against lateral movement.

4. In combination, a core drill, a gyroscopic compass mounted thereon and including a dial, a member movably associated with the drill to occu )y one position when the drill is in nonrilling position and adapted to engage the formation atthe bottom of the hole when the drill is in drilling position and be thereby moved to another position, and means operable when the member is in its first mentioned position to lock the dial against movement, and responsive to movement of member to its second men tioned position, to unlock the dial.

5. In combination, a core drill, a gyroscopic compass including an indicator, and means movably associated with the core drill and normally occupying a locking position with respect to the indicator to prevent movement of the latter, said means adapted to engage the formation in the hole when the drill is lowered into the latter and thereby be moved to an unlocking position with respect to the indicator.

6. In combination, a core drill, a gyroscopic compass includin an indicator, locking means for the in icator movable to occupy locking and unlocking positions, means for normally urging said means to locking position, said locking means adapted to engage the formation in the hole when the drill is lowered into the latter and thereby be moved to unlocking position against the action of said urging means.

ARTHUR L. ARMENTROUT. ELWIN B. HALL. 

